I don't know about the gassers, but Monaco use to put all the 12 volt fuses for the chassis in an outside bay under the driver's window, called the run bay.
Monaco occasionally powered two items off of one fuse, but labeled the fuse under the other item. For example, the radio and dash fans could run off the same fuse, yet Monaco labeled that fuse dash fan. Consequently, you often have to test each fuse with a meter to make sure its still good.
I like keeping one of these handy for testing fuses of all sizes. You can buy them at Walmart in the automotive section. You just touch the pointers to the fuse and it lights up if good.